Senate rules provide other ways beyond the now-curtailed filibuster to obstruct nominees. Hearings can be boycotted. Routine procedural approvals can be withheld. New Capitol Hill ambushes can be plotted, perhaps with tactics not yet seen. For a truly motivated minority, losing one weapon means it’s time to pick up another.

“My sense is the Republicans are going to be putting up whatever roadblocks they can, though they don’t have the main roadblock they used to have,” Russell Wheeler, a judiciary expert at the Brookings Institution, said in an interview Friday.

Republicans already flexed their muscles Thursday, the same day Senate Democrats weakened the filibuster by a 52-48 vote. Under the new rules, executive branch and most judicial nominations will require only 51 votes to proceed rather than the 60 required for legislation and Supreme Court nominations.

Using the prior filibuster rules, Republican lawmakers thwarted nominees, including Goodwin Liu, a University of California, Berkeley, law professor nominated to the 9th U.S. Circuit Court of Appeals. After falling short on a 52-43 Senate vote, Liu withdrew his nomination and now serves on the California Supreme Court. More recently, Republicans used the 60-vote margin to block three nominees to the U.S. Court of Appeals for the District of Columbia Circuit.

Some believe the diminished filibuster will encourage presidents to nominate more controversial candidates. For nominees, the rules change will certainly mean quicker approval.

No specific controversy shadows Los Angeles-based attorney John B. Owens or San Francisco-based attorney Michelle T. Friedland. Friedland even clerked for former Supreme Court Justice Sandra Day O’Connor, a Republican who showed up for Friedland’s confirmation hearing. Both were nominated Aug. 1 to the 9th Circuit, which handles appeals in nine Western states. Both sailed through their recent confirmation hearings.

And Texans Robert L. Hobbs and Gary L. Blankinship, nominated to serve as U.S. marshals, have similarly excited no partisan rancor.

Nonetheless, the nominees are now hostages of the Judiciary Committee’s eight Republicans. Members of both parties have practiced the no-show tactic, but its deployment Thursday reminded all that even a weakened minority retains arrows in its quiver.

“The Republicans have gotten a lot more aggressive in fighting nominations,” Wheeler said.

Data compiled by Wheeler shows that judicial vacancies are filled much more slowly in states with one or two Republican senators; suggesting, he said, that Republican lawmakers may be “simply slow-walking” the nomination process.

Richard Painter, a law professor at the University of Minnesota, cautioned in an interview Friday that Republicans should hesitate before they make “too big of a stink” over nominees, because of public discontent with a dysfunctional Congress. At the same time, Painter, a former chief ethics lawyer in President George W. Bush’s White House, noted that old-fashioned deal-making can work wonders.

“What you can do is say, ‘If you want Republican votes on anything else, like a treaty, then talk to us about judges,’” Painter said.

Another potential tool for Republicans is the Senate Judiciary Committee’s longstanding but still fluid “blue slip” tradition, by which the committee seeks a go-ahead from a state’s two senators. Committee chairmen decide how much weight to give the blue slips.

President Barack Obama, for instance, nominated at-large Circuit Judge Alison Renee Lee to a Columbia, S.C.-based federal judgeship in June. South Carolina’s two Republican senators have voiced some hesitation about Lee. No hearing has yet been set, though no one is saying the blue slips are being withheld.

But underscoring the potential for delay, Los Angeles native Rosemary Marquez is still awaiting a hearing for a U.S. District Court seat in Arizona for which she was first nominated in June 2011. At least some of the past delay has been caused by problems in getting the requisite blue slips from Arizona’s Republican senators.

If more Republicans start withholding blue slips, the Senate Judiciary Committee chairman could, in theory, eventually modify the tradition. That, in turn, could prompt yet another GOP escalation.

Supreme Court nomination tactics, the most consequential of them all, could escalate in several ways.

Individual senators, inflamed against the party in power and perhaps entranced by the spotlight, may now actually be more motivated to undertake a Supreme Court filibuster and less hesitant to break Senate comity. The willingness of Republican Sen. Ted Cruz of Texas earlier this year to obstruct a government funding bill underscored the increased clout today’s Senate grants a zealous politician.

Another result, now that the genie is out of the bottle, could be still more confirmation changes in the future.

“The silver lining is the day will come when roles are reversed,” predicted Sen. Charles Grassley of Iowa, the senior Republican on the Senate Judiciary Committee. “When that happens, our side will likely nominate and confirm lower court and Supreme Court nominees with 51 votes, regardless of whether Democrats actually buy into this fanciful notion that they can demolish the filibuster on lower-court nominees and still preserve it for Supreme Court nominees.”

Senate rules provide other ways beyond the now-curtailed filibuster to obstruct nominees. Hearings can be boycotted. Routine procedural approvals can be withheld. New Capitol Hill ambushes can be plotted, perhaps with tactics not yet seen. For a truly motivated minority, losing one weapon means it’s time to pick up another.

“My sense is the Republicans are going to be putting up whatever roadblocks they can, though they don’t have the main roadblock they used to have,” Russell Wheeler, a judiciary expert at the Brookings Institution, said in an interview Friday.

Republicans already flexed their muscles Thursday, the same day Senate Democrats weakened the filibuster by a 52-48 vote. Under the new rules, executive branch and most judicial nominations will require only 51 votes to proceed rather than the 60 required for legislation and Supreme Court nominations.

Using the prior filibuster rules, Republican lawmakers thwarted nominees, including Goodwin Liu, a University of California, Berkeley, law professor nominated to the 9th U.S. Circuit Court of Appeals. After falling short on a 52-43 Senate vote, Liu withdrew his nomination and now serves on the California Supreme Court. More recently, Republicans used the 60-vote margin to block three nominees to the U.S. Court of Appeals for the District of Columbia Circuit.

Some believe the diminished filibuster will encourage presidents to nominate more controversial candidates. For nominees, the rules change will certainly mean quicker approval.

No specific controversy shadows Los Angeles-based attorney John B. Owens or San Francisco-based attorney Michelle T. Friedland. Friedland even clerked for former Supreme Court Justice Sandra Day O’Connor, a Republican who showed up for Friedland’s confirmation hearing. Both were nominated Aug. 1 to the 9th Circuit, which handles appeals in nine Western states. Both sailed through their recent confirmation hearings.

And Texans Robert L. Hobbs and Gary L. Blankinship, nominated to serve as U.S. marshals, have similarly excited no partisan rancor.

Nonetheless, the nominees are now hostages of the Judiciary Committee’s eight Republicans. Members of both parties have practiced the no-show tactic, but its deployment Thursday reminded all that even a weakened minority retains arrows in its quiver.

“The Republicans have gotten a lot more aggressive in fighting nominations,” Wheeler said.

Data compiled by Wheeler shows that judicial vacancies are filled much more slowly in states with one or two Republican senators; suggesting, he said, that Republican lawmakers may be “simply slow-walking” the nomination process.

Richard Painter, a law professor at the University of Minnesota, cautioned in an interview Friday that Republicans should hesitate before they make “too big of a stink” over nominees, because of public discontent with a dysfunctional Congress. At the same time, Painter, a former chief ethics lawyer in President George W. Bush’s White House, noted that old-fashioned deal-making can work wonders.

“What you can do is say, ‘If you want Republican votes on anything else, like a treaty, then talk to us about judges,’” Painter said.

Another potential tool for Republicans is the Senate Judiciary Committee’s longstanding but still fluid “blue slip” tradition, by which the committee seeks a go-ahead from a state’s two senators. Committee chairmen decide how much weight to give the blue slips.

President Barack Obama, for instance, nominated at-large Circuit Judge Alison Renee Lee to a Columbia, S.C.-based federal judgeship in June. South Carolina’s two Republican senators have voiced some hesitation about Lee. No hearing has yet been set, though no one is saying the blue slips are being withheld.

But underscoring the potential for delay, Los Angeles native Rosemary Marquez is still awaiting a hearing for a U.S. District Court seat in Arizona for which she was first nominated in June 2011. At least some of the past delay has been caused by problems in getting the requisite blue slips from Arizona’s Republican senators.

If more Republicans start withholding blue slips, the Senate Judiciary Committee chairman could, in theory, eventually modify the tradition. That, in turn, could prompt yet another GOP escalation.

Supreme Court nomination tactics, the most consequential of them all, could escalate in several ways.

Individual senators, inflamed against the party in power and perhaps entranced by the spotlight, may now actually be more motivated to undertake a Supreme Court filibuster and less hesitant to break Senate comity. The willingness of Republican Sen. Ted Cruz of Texas earlier this year to obstruct a government funding bill underscored the increased clout today’s Senate grants a zealous politician.

Another result, now that the genie is out of the bottle, could be still more confirmation changes in the future.

“The silver lining is the day will come when roles are reversed,” predicted Sen. Charles Grassley of Iowa, the senior Republican on the Senate Judiciary Committee. “When that happens, our side will likely nominate and confirm lower court and Supreme Court nominees with 51 votes, regardless of whether Democrats actually buy into this fanciful notion that they can demolish the filibuster on lower-court nominees and still preserve it for Supreme Court nominees.”